1. Field of the Invention
This invention generally relates to portable cartridges containing diversified input material for programming, being recorded upon, and/or operating such central components. Such cartridges are used in tape recorders, microfilm readers, motion picture cameras, and microprocessors.
2. Description of the Prior Art
Recently, the TV game industry began selling consumer video games with microprocessors. These microprocessors permit the owner of such a game to purchase inexpensive cartridges that can program the processor. Each cartridge contains an electronic micro-circuit, and with a plurality of such cartridges, a player can program a single processor to display hundreds of video games.
One of the problems that has developed in the manufacture and use of these cartridges has been in electrically shielding the electronic micro-circuit. These cartridges are designed to be handled by the players of the game and are therefore subject to the build-up of large potentials of static electricity. Static electricity can discharge into the small traces on the circuit board and either fuse the traces together or destroy them entirely. A TV game cartridge is especially vunerable because it contains at least one read-only memory (ROM) which is highly sensitive to static discharge.
Prior approaches to the problem of shielding these circuits have used shorting bars which short all of the traces together when the circuit is not in use. These shorting bars distribute any static electricity equally across all of the traces and tend to dissipate its effect. A second approach has been to keep the circuit board at least a quarter of an inch away from an opening or any exposed surface of the cartridge. Although static electricity can develop very high potentials, a modest air gap can stop most discharges.
Another problem in the manufacture of TV game cartridges for consumer use has been in designing these cartridges to resist inquisitive tampering and to withstand physical damage to the electronic micro-circuits within the cartridges. Children particularly have an innate desire to open the cartridges and inadvertenly damage the traces both on the circuit board and in the connector of the micro-processor.
Prior approaches to combat this problem have relied on designing impenetrable housings and the use of traces and circuit components that can withstand all but malicious damage.
In general, however, no TV game manufacturer has heretofore developed a cartridge that is both relatively tamper proof, resistant to static electricity, and inexpensive to manufacture.